The recovery of nucleic acids from a solid or semi-solid collection matrix is widely accepted in molecular diagnostics. Typical examples of matrices include swabs and paper substrates. Recovery of nucleic acids from these materials can be challenging because of inefficient extraction from the substrate material and potential interference from the material with pipetting or other liquid handling devices. In addition, the presence of a solid substance in an instrument can trigger an Error signal, resulting in an aborted extraction or other delay.
Efficiency of recovery of nucleic acids can be enhanced by use of harsh and/or toxic conditions such as phenol/chloroform, and indeed this has been attempted with polymeric swabs. Existing solid substrates, however, are not soluble in guanidinium and other milder chaotropic solutions.